Hydrodynamic Performance of a Ring-Style High-Shear Impeller in Newtonian and Shear-Thinning Fluids

Laminar mixing of Newtonian and shear-thinning fluids induced by a Hockmeyer®-type impeller was investigated. Two unbaffled tanks at three impellers off-bottom clearances (c) were studied. Six geometric combinations, i.e., two d/T and three c/T, were examined where d and T are the impeller and tank diameters, respectively. Determination of the Metzner-Otto constant (K_s) was undertaken. The effects of d/T, c/T, and fluid rheology on K_s, power demand, pumping, shear and viscous dissipation were analyzed. The evaluated geometric ratios and rheology do not significantly affect K_s and power demand, only the rheology had an impact on the remaining hydrodynamic parameters. Pumping was favored with the Newtonian fluid, and shear and viscous dissipation increased with the shear-thinning fluid.     

Resurgence of minority and autochthonous grapevine varieties in South America: a review of their oenological potential

In contrast with the general trend of producing wine from the most famous grapevine varieties, associated with the French paradigm, such as Cabernet-Sauvignon, Merlot, Pinot Noir, Syrah, Sauvignon Blanc, and Chardonnay, there is a tendency to revalorize and preserve minority or autochthonous grapevine varieties worldwide. The South American wine region, where most of the varieties derived from varieties brought after European colonization, is not exempt from this. This has allowed new wines to be provided with distinctive identities that are markedly different from the current homogeneous wine production. Moreover, varietal homogenization increases vineyard genetic vulnerability in relation to the emergence of grapevine diseases, to which the commonly cultivated varieties are not resistant. This review summarizes the oenological potential of minority or autochthonous grapevine varieties cultivated within the South American wine region, focusing on Argentina, Chile, and Bolivia. © 2019 Society of Chemical Industry     

Sperm oil replacements from selectively hydrogenated soybean and linseed esters: Special lubricants

Soybean and linseed oils were selectively hydroenated with copper-on-silica gel catalyst. The linolenate content of the oils was reduced to diene and monoene with no appreciable increase in saturates. Hydrogenated soybean oils contained 68–76% monoene, 11–18% diene, 0% conjugated diene and triene, 1–6% conjugatable diene, 0–0.3% conjugatable triene, and 23–40% isolatedtrans double bonds. Hydrogenated linseed oils contained 44–54% monoene, 35–45% diene, 0% conjugated diene and triene, 0–7% conjugatable diene, 0–02% conjugatable triene, and 44–59% isoaltedtrans double bonds. Esters of fatty acids, derived from these selectively hydrogenated oils, were prepared with trimethylolethane, trimethylolpropane, trimethylolbutane, pentaerythritol, ethylene glycol, C₁₈ saturated cyclic alcohols, primary C₁₂–C₁₈ saturated (nC₁₂, nC₁₄, nC₁₆, nC₁₈) alcohol, and primary C₁₆–C₁₈ saturated (nC₁₆, nC₁₈) alcohol blends. Measurements of viscosities and of smoke, flash, and fire points indicate that these esters are possible replacements for sperm oil. Certain of them, after sulfurization, also have potential as extreme pressure lubricant additives. Presented at the AOCS meeting in Philadelphia, September 1974.     

3D Patterning within Hydrogels for the Recreation of Functional Biological Environments

Biological structures are inherently complex in nature. Structural hierarchy, chemical anisotropy, and compositional heterogeneity are ubiquitous in biological systems and play a key role in the functionality of living systems. For decades, methods such as soft lithography have enabled recreation of such arrangements through precise spatial control of molecular patterns in 2D. With technological advances and increasing understanding of molecular and structural biology, there has been an increasing interest in recreating such spatial organizations in 3D. In this review, a comprehensive summary of the latest technologies being used to create 3D patterns of functional molecules within hydrogels for tissue engineering applications is presented. The review is divided into five groups of technologies defined according to the main driving force used to fabricate the patterns including light, precise chemical design, microfluidics, 3D printing, and non-contact forces (i.e. electric, magnetic, or acoustic fields and self-assembly).     

Polyesteramides from linseed oil for protective coatings low acid-value polymers

Linseed and soybean diethanolamides, from the sodium alkoxide-catalyzed reaction of the corresponding oil with diethanolamine, were used as diols to prepare a series of polyesteramides. The diols and dibasic acids or anhydrides were heated in refluxing xylene until the theoretical amount of water was collected in a trap. Low acid-value linseed polymers were prepared with 10, 20, and 30 mole percent excess diol over the dibasic acid, and the effect of the excess diol on molecular weight, viscosity, and film properties of the polymers was examined. Polyesteramides which contained 10 mole percent excess fatty diethanolamide were made with 11 dibasic acids or anhydrides. The polymers were brown-orange oils with Gardner viscosities of Z7 to >>Z10. Number-average molecular weights ranged from 2,200 to 5,200. Data on drying characteristics, hardness, and chemical resistance of films were obtained. The better polymers air-dried rapidly to give hard, glossy films (Sward rocker 20–60). Films baked at 190C for 10 min were softer than the corresponding air-dried films. Xylene resistance of soybean and linseed polymer films was generally excellent, and alkali resistance was moderate. Soybean films showed the better alkali resistance. Presented at Division of Organic Coatings and Plastics Chemistry, 153rd ACS meeting, Miami Beach, Fla., April 1967. No. Utiliz. Res. Dev. Div., ARS, USDA.     

Thermal decomposition of diethyl ketone triperoxide in methyl methacrylate: Theoretical and experimental study of the initial solvation state and its influence on the polymerization process

The decomposition rate constant (k_d) of diethyl ketone triperoxide (DEKTP, 3,3,6,6,9,9‐hexaethyl‐1,2,4,5,7,8‐hexaoxacyclononane) in methyl methacrylate (MMA) was determined by the kinetic study of its thermal decomposition at temperatures from 110 to 140°C. The calculated k_d for DEKTP in MMA was 2.4 times lower (at 130°C) compared with that previously determined and reported in styrene (St). Density functional theory (DFT) calculations demonstrated that the decomposition of DEKTP molecule in MMA required higher interaction energy than in St, thus explaining its lower k_d value. Bulk polymerization kinetics of MMA using DEKTP as the initiator revealed the presence of an induction period, in contrast with St polymerization, providing clear evidence of the solvation state influence at early polymerization stages. This work provides mechanistic insights into the interactions among the multi‐functional cyclic peroxide DEKTP and vinyl monomers; St and MMA, and their influence on the polymerization kinetics. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42905.     

Consumer perceived healthiness and willingness to try functional milk desserts. Influence of ingredient,ingredient name and health claim

A conjoint study was carried out in order to study the influence of two functional ingredients (antioxidants and fiber), the name used to declare the addition of the ingredient (common vs scientific name), and the type of health claim (no claim, ‘enhanced function’ and ‘disease reduced risk’ claims) on consumers’ perceived healthiness and willingness to try functional milk desserts.The use of compounds or scientific names might not be recommended as they could have a negative impact on consumers. If a functional food manufacturer wants to emphasize the use of a novel ingredient, the ingredient could be declared using its scientific name but incorporating a health claim on the label, in order to achieve a positive association in consumers’ mind between the ingredient and its health effect. Besides, consumers showed the same attitude towards ‘enhanced function’ or ‘reduced disease risk’ claims.Women and old people seemed to be the most positive groups toward the evaluated functional foods. Women gave more importance than men to the type of name used to declare the addition of the functional ingredient, which could be probably attributed to the fact that women are more familiar with the health effects of fiber and antioxidants than men. Besides, young people emphasized the disease preventing claims, while older people tended to be also interested in claims that focus short term effects on health.     

Adversarial classification using signaling games with an application to phishing detection

In adversarial classification, the interaction between classifiers and adversaries can be modeled as a game between two players. It is natural to model this interaction as a dynamic game of incomplete information, since the classifier does not know the exact intentions of the different types of adversaries (senders). For these games, equilibrium strategies can be approximated and used as input for classification models. In this paper we show how to model such interactions between players, as well as give directions on how to approximate their mixed strategies. We propose perceptron-like machine learning approximations as well as novel Adversary-Aware Online Support Vector Machines. Results in a real-world adversarial environment show that our approach is competitive with benchmark online learning algorithms, and provides important insights into the complex relations among players.